ADSORPTION AND WETTING PHENOMENA FOR COLLOIDS IN LIQUID-MIXTURES

Colloidal particles suspended in a binary liquid mixture display many interesting features. For instance, a preferential adsorption occurs that is more important on the side of the coexistence curve which is poor in the adsorbed component. Adsorption increases with the proximity of the mixture to the coexistence curve. An aggregation phenomenon which is reversible with respect to temperature is observed in the high adsorption regime close to the bulk coexistence. A robust set of observations, involving different colloids and liquid mixtures, is presented. The above findings are assessed in the light of current theoretical understanding of wetting phenomena. In addition, the recent advances in the dynamics of aggregation of colloids, and the inverse process, fragmentation, are discussed.